Thanks for posting and welcome to the Bose Community. I am so sorry to read that you are having issues with one of your Companion 2 speakers and would love to point you in the right direction to resolve this.
We don't sell singular internal parts for any of our speakers meaning that you will need to reach out to our customer support team to get this speaker repaired, you can reach the team via clicking this link, then kindly scroll and select your region, once this is done please scroll to Contact Us. The team will be on hand and ready to help.
Please update us on the result of your call with the team!